Queen's Gambit Declined: Baltic Defense, Queen Attack Deferred
ECO D06
Move order
1. d4 d5 2. c4 Bf5 3. Nc3 e6 4. Qb3
Ideas
ECO D covers queen-pawn games and closed structures, including many Gambits and the Queen's Gambit complex. White builds a pawn center and keeps the position more closed than after 1. e4. This entry tracks a longer branch in the opening tree. Use the diagram and SAN list to recognize the tabiya, then try the line against Maia to explore typical plans in practice.